package main.java.unsafe;

import java.util.*;
import java.util.concurrent.CopyOnWriteArrayList;

public class LIstTest {
    public static void main(String[] args) {
        // 并发下 arrayList 并不安全
        /**
         * 解决方案
         * 1 List<String> list = new Vector<>();
         * 2 List<String> list = Collections.synchronizedList(new ArrayList<>());
         * 3 List<String> list = new CopyOnWriteArrayList<>();
         */

        List<String> list = new CopyOnWriteArrayList<>();
        for(int i = 1;i<=10;i++){
            new Thread(()->{
                list.add(UUID.randomUUID().toString().substring(0,5));
                System.out.println(list.toString());
            },String.valueOf(i)).start();
        }
    }
}
